Material recycling has become an important industry in recent years due to decreasing landfill capacity, environmental concerns and dwindling natural resources. Many industries and communities have adopted voluntary and mandatory recycling programs for reusable materials. Until recently, most trash collection efforts delivered waste materials, separated at the source, e.g. by the home owner, to the Material Recovery Facilities (MRF). In an effort to improve the economies of collecting garbage for recycling, many municipalities have changed from curbside source-separated to commingled recycling methods. Solid waste and trash that are collected from homes, apartments or companies now are combined in one container. When brought to a waste processing center, or MRF, the recyclable materials are frequently mixed together in a heterogeneous mass of material. These mixed recyclable materials include newspaper, magazines, mixed paper, cardboard, aluminum cans, plastic bottles, glass bottles and other materials that may be recycled. Changes in MRF design were required to handle the new commingled material.
U.S. Application #20030062294 (1) is an example of equipment developed to separate what is termed “single-stream” waste into fractions which have economic value. The single most valuable recyclable waste product is newspaper and other paper based product. The products of CP Manufacturing, as exemplified in the above application and also in U.S. Pat. No. 6,460,706 (2), are focused primarily on recovering paper, plastic containers and metal cans. These items may represent 70 to 90% of the economic value in recyclable waste as it is constituted today.
The advent of this equipment, by the nature of its operation, created its own waste by-product which is typically sent to a landfill. This material is referred to as “−4 inch news screens fines” (NSF). It is aggregates of compressed waste which fall through the first operation of the conventional disc screening method; based on the separation of the discs it is less than 4 inches in at least two dimensions; these dimensions vary somewhat with the particular equipment and operator. This material is a combination of glass, paper, metallic objects and general refuse, including food wastes. Historically, no equipment or process has been available to process this trash for sufficient residual value and hence the disposition to a landfill. There is an environmental need to reduce the amount of waste going to landfills and a need to compensate the MRF operator for this service.